Major depressive disorder (MDD) is one of the most prevalent psychiatric disorders and a leading cause of disability worldwide. Existing therapies fail to produce complete recovery. Progress toward improving outcome must include innovations that are safe, powerful, inexpensive and simple (for fast and effective dissemination). The proposed research seeks to test one such innovation. We seek to improve outcome by improving memory for the content of cognitive therapy (CT) sessions. CT is one of the most promising approaches to the treatment of MDD, yet there is room for improvement. We believe that adding memory enhancing strategies to CT may improve MDD outcome because: (a) MDD is often characterized by memory impairment, (b) there is evidence that the memory impairment is modifiable, (c) CT typically entails the activation of emotion, (d) emotion can impair or bias memory and (e) there is evidence that memory for the content of therapy sessions is poor. Aim. To evaluate if the addition of a novel strategy, derived from the memory literature and designed to enhance memory for the content of CT sessions, will improve treatment outcome for MDD. Cognitive support involves a series of specific procedures that support the encoding and retrieval stages of an episodic memory. It is hypothesized that CT+Cognitive Support, relative to CT-as-usual, will be associated with improved depression outcome at the end of treatment and 6 months after the completion of treatment. Research Plan. Phase 1 involves an iterative process of developing and refining the cognitive support intervention by testing the treatment with adults with MDD (n = 8). In Phase 2, a small pilot feasibility RCT will be conducted on adults with MDD (n = 48) who will be randomized to either: (a) CT+Cognitive Support (n = 24) or (b) CT-as-usual (n = 24). Outcome measures will be taken at baseline, end of treatment, and 6 months after treatment. Long-term objective. The outcomes, if positive, will have major public health implications because simple, inexpensive memory enhancing strategies can be readily included as a standard feature in all psychosocial treatments for a broad range of mental illness. As a first step toward achieving this goal, this research will provide the pilot data needed to prepare a larger scale intervention study focused on improving outcomes by improving memory for the content of therapy sessions in MDD. PUBLIC HEALTH RELEVANCE: Existing drug and talking therapies for major depressive disorder (MDD) fail to produce complete recovery. This study will determine if substantial improvements to one of the most promising therapies, cognitive therapy (CT), can be achieved by administering a carefully designed procedure to improve memory for the content of CT sessions. This is important because (a) memory deficits are common in MDD patients and (b) each CT therapy session typically covers a complex array of topics and various skills are taught.